set optimization from -O2 to -O3, 3.4 % performance increase observed#278
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andreasbuhr wants to merge 1 commit intolh3:masterfrom
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set optimization from -O2 to -O3, 3.4 % performance increase observed#278andreasbuhr wants to merge 1 commit intolh3:masterfrom
andreasbuhr wants to merge 1 commit intolh3:masterfrom
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+1. Any reason not to merge this PR? |
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I've seen a runtime decrease of 3.4% on average over three runs in one example raising the optimization level from -O2 to -O3 in gcc.
bwa uses lots of bit shift operators. It seems -O3 makes a difference here, see this trivial example:
https://www.godbolt.org/z/jD_cC5
I aligned one million reads to a mm10 using the command line
bwa aln -t 4 -f reads.sai mm10.fa Andreas_BWA/SRR1519948.1_1000000.fastqTime went down from 62.8s to 60.6s.